Caul (sp?) question

[Sean Troy]

Will 3/4" or 1" pipe clamps make for a good caul? Thanks, Sean

[glenn bradley]

In our context a caul is usually a piece of wood, often bowed (http://www.bowclamp.com/), that is placed between the object being clamped and the clamp heads to more efficiently and evenly distribute pressure. Many of us make our own but the quality and consistency of BowClamps makes them a good deal. That being said I am not sure I understand your question.

[John Coloccia]

It would probably work fine except that you may have a heck of a time getting a clamp to stay on the curved surface. What's you're application? If you're doing what I think you're doing, you'd typically want on end curved (just so that you concentrate the pressure where you need it) and the other end, the side that goes against the clamp, flat.

[Darnell Hagen]

If you are using it to clamp the middle of a joint, say a shelf dadoed into a bookcase side, the caul should be bowed to increase pressure on the middle of the joint.
If you are using it as a clamp pad, say in a tabletop glueup, they work very well, as long as the pipe is the same diameter as the top is thick. Then the pressure is exerted on the centre of the stock.

[Mike Henderson]

In general, a piece of pipe will not make a good caul because it's not stiff enough. The flex in the pipe means the center will not receive much pressure.

You can find a tutorial on making your own cauls here (http://www.mikes-woodwork.com/Cauls.htm).

Mike

[Sean Troy]

Thanks for the info. I was thinking a pipe clamp used to keep the glue up from bowing upward as clamp pressure was applied from the sides. I see why you would use the bowed wood to apply pressure. making my own would be a fun project. thanks, Sean

[Prashun Patel]

In that sense, yes, a pipe clamp will be fine - however consider that snugging the pipe up to the boards may cause staining, so either cover the line with tape, or use a 'real' caul instead. I'm sure u know to alternate the clamps on each side of the board.

Curved cauls out of 2x4's are easy enough to make - especially if you have a jointer.